Who could have thought that Bryn Terfel’s 11th-hour departure from the Ring could have been the making of Keith Warner’s production? And yet, against the odds, it’s John Tomlinson’s grizzled, craggy and desperately tragic Wotan that has been the emotional glue holding this cycle together.

Siegfried might be the story of the world’s greatest hero, but it is also the story of Wotan’s endgame. And that endgame seems far clearer this time than it did when Tomlinson first sang the part two years ago, without the benefit of the role’s two previous incarnations. When Erda (a Miss Havisham-like Jane Henschel) tells him: “You are not what you believe yourself to be”, we see that analysis writ large in Tomlinson’s burning desire to manipulate events of which he is no longer in control.

Again, too, we’re reminded of the duality between him and Peter Sidhom’s potent, pathetic Alberich when the two come together for a strangely poignant reunion in Act II. It’s only after John Treleaven’s naively destructive Siegfried casually breaks Wotan’s spear that he finally, devastatingly, gets the message: a new world order is on its way.

Other elements of Warner’s vision are also coming into focus. We first saw an aeroplane as a toy model in Das Rheingold, a design dreamt up in the laboratory of Nibelheim; its reappearance as a pile of debris in Act I reminds us that Mime’s magic is continuing to wreak its havoc across the world. The stylised forest in Act II no longer seems quite so ridiculous now that its animal denizens aren’t hustled on by stagehands but glide around by themselves. It’s a pity that Phillip Ens’s Fafner still puts up precious little fight as a dragon, but as a singing severed head he strikes exactly the right Hammer Horror note.

That said, Stefanos Laziridis’s grey sets still seem no place to put the nature-loving Siegfried. No matter how sweetly Ailish Tynan chirrups as the Woodbird, Warner seems embarrassed by this pastoral interlude. She’s a puppeteer as synthetic as the plastic grass, and what Siegfried’s role in this pantomime means is unclear.

And Treleaven just doesn’t fill the gap. He’s always a puppyish, eager presence, but there’s a sad lack of bloom (or accurate pitching) to his singing, and by Act III’s climactic duet with Lisa Gasteen’s sensitive Brünnhilde (still hard-pressed on top, which counts in Siegfried more than anywhere else) he was struggling. In truth, it’s far easier to warm to Gerhard Siegel’s superlative Mime, who blends expertly his shambling sitcom routines with blackly malevolent intent.

But one man knows how much this hero counts: Antonio Pappano, whose handling of the orchestra touches greatness in its explosive charge and transcendent beauty. Siegfried is the perfect outlet for his singer-friendly dynamics and chamber-like textures, but it’s Pappano’s triumph to tap into the anarchic energy of Siegfried himself: a force so uncontrollable that it will lead to the end of the world – to be precise, tonight’s Götterdämmerung.

Box office: 020-7304 4000

Editor's choice

• The 100 Best Films of the Decade
• 70 facts you didn't know about Marvel
• The 50 Biggest Movies Of 2010